The aerospace industry has developed designs for microsatellites and nanosatellites. This development of small space systems is likely to increase with new technologies that can be used to incorporate multiple functions in a small satellite. In U.S. Pat. No. 6,300,158 titled Integrated Solar Power Module, a method is described for producing thin film solar cells that are integrated with a multilayer printed wiring board and power processing electronics. However, the integrated solar power module does not address the problem of rejecting excessive heat produced by the active electronic components that are mounted on the back of the thin film solar cell substrate.
Active electronic components convert some of the electrical energy passing through the electronic components into heat. Most electronic components have maximum junction operating temperatures in the 80° to 125° C. range. The operating temperature of the thin film solar cells is in the 70° to 80° C. range. These thin film solar cells must reject excessive heat produced by the mounted electronic devices to maintain an operating temperature below the maximum operating temperature for the thin film solar cells. Further refinements of the integrated solar power module may have some portions of the thin film solar cell coated with a material that would have a low solar radiation absorptance and high thermal emissivity for maintaining the solar cells within a desirable temperature range. The entire solar cell assembly and current collectors are covered with a transparent polymer coverglass, which provides a front surface that has a high thermal emissivity. The existing design of the thin film solar cells presently has large silver current collectors located on the front of the solar cells. The silver collectors are silver bus bars that are highly reflective and have a low solar absorptance. The bus bars and solar cell structure obstruct thermal transmission through the solar cell. The amount of additional thermal energy that can be rejected from a thin film solar cell that has mounted active heat producing components is limited. These and other disadvantages are solved or reduced using the invention.